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arXiv · 1901.08283

Bounce in GR and higher-order derivative operators

Gen Ye·Yun-Song Piao
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Abstract

Recent progress seems to suggest that one must modify General Relativity (GR) to stably violate the null energy condition and avoid the cosmological singularity. However, with the higher-order derivative operators of scalar field (a subclass of the degenerate higher-order scalar-tensor theory), we show that at energies well below the Planck scale, fully stable nonsingular cosmologies can actually be implemented within GR.

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Gen Ye, Yun-Song Piao. 2019-01-24. Bounce in GR and higher-order derivative operators. https://doi.org/10.1103/physrevd.99.084019

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